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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 50401 to 50450:

  1. Matt Ridley Risk Management Failure Deja Vu
    Excellent analogy, Bert@24! The first of such kind that I've seen. I hardly make a post without useful input of mine but this time I make an exception and rest my post just on the applaud to you. Your little debunking analogy is worth exposing and repeating everywhere in popular media.
  2. New research from last week 51/2012
    The classic of the week, being a summary for policymakers rather than a pure sicentific source; contains some inconsistent claims. What cought my attention is how, on page2 column2, they speculated the warming effect of CO2. First, they estimate: "if CO2 reaches 400ppmv, the temperature will rise by 1.4F which may happen by 2010". That was quite good guess, provied they did not have Charney climate sensitivity back in 1970. They just had Charlie Keeling 12y record of CO2 and well established GHG band absorption theory, including WV feedback. Then, in the next paragraph, they claim: "if all available fosil fuel is burned and one half of the resulting CO2 were added to the atmosphere and there were no compensating effect, then the Earth's temperature would increase by 2F to 3F". That's way too small even within the context of this article only. They even have over-estimated the recoverable coal as 7600Gt (well that's the possible C flux we estimate today including permafrost and methane clathrate melt) which would mean more than 20 times the amount of C we burned to day. And that would have 2F to 3F warming potential only? Clearly that classic has no value as historical/scientific piece. Perhaps it has value because it shows that back then, even poliicians have not been talking about "global cooling threat" as contrarians would like to see.
  3. Bert from Eltham at 10:26 AM on 25 December 2012
    Matt Ridley Risk Management Failure Deja Vu
    When I was learning how to fly in the late seventies my instructor put this hood thing on my head so I could only see my instruments or dash and not outside. This exercise was designed to teach a mere beginner like me to never fly in clouds or lose sight of the real horizon or worse at night. He gave me the usual instructions to climb/descend and turn to set headings and various combinations. He then asked me to climb to 7000ft on a heading of 135. I knew there was cloud higher than we were and sure enough we were in thick cloud. I could tell by the sudden dimming of the light. He then put me through a lot of turns climbs and descents and combinations of all these. After about twenty minutes he said 'You do know how to fly on instruments! You were not cheating!' I then told him it was a simple matter to just cross correlate all the instruments to give a true indication of the state of the aircraft. Working in science had given me this insight. Further if you rely only on one instrument and ignore all others you will crash. Even if you look at all and fail to cross correlate and not see the pattern you still crash. The usual control failure is a spiral descent at ever increasing speed into the deck. This is analogous to the deniers flying. They will point to one instrument and say all is good. If that one changes they will find another that tells them all is OK. They then put absolute trust in the balance centre in their ear (natural cycles) . They then ignore that their airspeed is increasing, engine revs are increasing, they are losing height and the artificial horizon looks 'stuck' at some impossible angle. The heading is varying a bit but that is due to the wind! All is fine until you hit the deck at a velocity higher than V never exceed for your aircraft. This chap Ridley has crashed a bank and he now knows how to drive a planet! Bert
  4. Powerpoint friendly version of SkS Christmas cartoon
    Looks like most of the UK this Christmas! http://www.bbc.co.uk/news/uk-20493378
  5. Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    curiousd @68, I take it that you are asking about the small upward spike at the center of the CO2 absorption band rather than the large notch in the outgoing radiation caused by CO2 absorption and re-emission that Sphaerica has explained. The upward spike occurs in the point of strongest absorption by CO2. Because it is the point of strongest absorption, it requires less CO2 to absorb all (or most) of the upwelling radiation from below at that wavenumber. Consequently, CO2 at a higher altitude is able to absorb all upwelling radiation than is the case at neighbouring wavenumbers. Conversely, of course, there is stronger emission from higher altitudes at that wavenumber than from neighbouring wave numbers. These facts, together with the temperature profile of the atmosphere have interesting consequences: If you look down at 5km on the modtran program (default settings), you will see no central spike. That is because the high density is such that the greater absorptivity only makes a small difference in the average altitude of emission of upwelling radiation at that altitude. A small difference in altitude means a small difference in temperature, and hence little difference in the energy emitted. At 10 km there is a small downward spike at that wavenumber. Because 10 km is below the tropopause, higher means cooler, so emission from a higher altitude emits less energy. Again, however, because of the reasonably high density, the altitude difference is small. At 18 km, the small downward spike disappears again, although it was present at 17 km. The reason it disappears is that 18 km is the tropopause, so the small difference in altitude makes no difference in temperature, and hence emissions. At 20 km, a small upward spike appears. That is because the average altitude of emission for the wavenumber of strongest absorption is now in the stratosphere, and has a higher temperature than the neigbouring wavenumbers, whose average altitude of emission are still in the tropopause. At 30 km, the central spike is much taller. That is because the less dense atmosphere at this altitude results a greater altitude difference from the greater emission/absorption at that wavenumber, so the average emissions are from significantly higher. You will also notice, however, that the emissions from neigbouring wavenumbers are also higher than those at 20 km, indicating that the average altitude of emission to space at those wavenumbers has risen above the tropopause into the stratosphere. Despite this, total upward radiation has fallen nearly 1 W/m^2 compared to at 20 km. That is partly due to increased absorption by ozone, and partly because the average altitude of radiation to space in the wings of the CO2 notch is sill rising within the troposphere, resulting in reduced upward radiation. As move the look down altitude further up, upwelling radiation increase again, by about 1.5 W/m^2; but the basic shape of the CO2 absorption spectrum remains the same. It is important to note that the modtran model does not respond dynamically to increased CO2. Increasing CO2 increases the effective altitude of radiation to space. A simplistic understanding of this might suggest, from the fact that increased altitude shows increased upward radiation above 30 km, that increased CO2 will not decrease TOA IR radiation. In fact, that is not the case, even with no dynamic response, as can be shown by doubling CO2 in a modtran experiment. Further, increasing CO2 increases the height of the tropopause slightly, and significantly cools the stratosphere and hence the increase in emissions in the central regions of the CO2 notch with altitude above the tropopause. That means the Modtran model underestimates the reduction in IR radiation to space with increased CO2. Note also that different latitudes and seasons have very different temperature profiles, which makes a significant difference to the effect of change in lookdown altitude.
  6. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    Sphaerica "How are the exiting farmers in Texas, Oklahoma and the rest of the US Midwest supposed to react to this?" Russian passports? Seems that the Ruskies won the cold war after all. :-)
  7. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    Villabolo, Yes. Some people seem to love to rather simplistically belief that agriculture can simply move further north, without considering that:
    • The length of the growing season (available sunlight and length of day) is shorter
    • The soil was scraped away during the previous glacial period, and it takes thousands of years of growth to replace such soil
    • How are the exiting farmers in Texas, Oklahoma and the rest of the US Midwest supposed to react to this?
    • Now we're going to clear that many more tens of thousands of square miles of forest, further adding CO2 to the atmosphere, in order to make room for all of those farms?
  8. Solar Cycle Model fails to predict the recent warming
    JRT256, Your comment is puzzling. Did you actually read the post? Sunspot cycles and variations and cosmic rays are definitively not currently warming the Earth's climate, since those factors have been on the decline for the past thirty years. As such, while there is some chance that they have a small influence on climate, this influence must be negative, and yet is clearly being vastly overwhelmed by CO2. Why is it that you think the above post does not answer "the question currently being asked?"
  9. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    John Russell @ #8 Wasn't meant as a criticism. :-) I could imagine what will happen to storm lashed refineries, pipe lines, and tar sands' pits.
  10. Subcap Methane Feedbacks. Part 3: Methane from beneath the ice
    There may be a couple of further wrinkles to this story http://mtkass.blogspot.co.nz/2011/08/end-of-ice-ages.html
  11. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    villabolo #7 I'm sure you're right (though you're making my point about 'positives'). Never mind, they'll be too busy mining tar sands, minerals and pumping Arctic oil to notice.
  12. 2012 SkS Weekly Digest #51
    Hey Guys It's time we stopped obsessing about the climate deniers and just got on with documenting the changing climate. It's a shame to keep giving them oxygen as if they have something worthwhile to say. They remind me of someone standing on a beach during an earth quake denying that Tsunami's exist. They are irrelevant and becoming more so as the months roll on.
  13. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    John Russell @4: "From a human perspective we can expect much turmoil, in geo-political terms, as areas nearer the equator could eventually become uninhabitable and food production is forced to migrate latitudinally. I guess Canada, Siberia, Greenland and Svalbard become power houses of a new economy..." My understanding is that the soil in Canada's boreal forests is thin, rocky and acid. The acidity can be neutralized with lime though you'll need large amounts. The rockiness will make mechanized agriculture difficult. What's more, the albedo change in the arctic will guarantee that there will be more intense storms in that region which can ruin crops.
  14. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    @Terranova #3: Here is an example of a negative result on the Siberian permafrost. Of you're thinking of agriculture in that region, heavy equipment simply will not be able to operate in swampland. The only positive result I can think of is that the vegetation growing in this muck may slow down the CO2 build up by a bit. Other than that, it is not to our benefit to have increased levels of methane.
  15. 2012 SkS Bi-Weekly News Roundup #11
    @Paul.H #3: My commentary under the SkS Highlights heading stems from what I have observed happening in the USA. It may or may not be reflective of what’s happening in other countries of the world. On a global scale, the ever-growing body of climate science is quite robust. The willingness of world leaders in both the public and private sectors to embrace what the science is telling us and to take appropriate actions to prevent a future global climate catastrophe is currently severely lacking.
  16. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    @Trranova #3: The detail that you are looking for is embedded in the NOAA report itself, i.e., Arctic Report Card: Update for 2012 .
  17. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    @Terranova, #3 I'm not really sure what your point is. I guess it depends on what we define as 'negative' and 'positive'. Clearly some species will see their habitat shrinking, while other species will experience improving conditions and a population explosion. So is that positive or negative? For the oil companies it's already clear that they see the Arctic as a land of opportunity, as do shipping companies wishing to send their cargoes over 'the top of the world'. Positive or negative? The problem is we're taking a world that's to a large extent been in a reasonably steady state and we're giving it a really good shake up; not by intent but as a side effect of our activities. Eventually, of course, it will all settle again into a new and different equilibrium, but in the meantime you can expect turmoil amongst all species of flora and fauna with much 'collateral damage'. Positive or negative? From a human perspective we can expect much turmoil, in geo-political terms, as areas nearer the equator could eventually become uninhabitable and food production is forced to migrate latitudinally. I guess Canada, Siberia, Greenland and Svalbard become power houses of a new economy and we leave the Mediterranean, Middle East, India and Central America to stew in their own juice. Positive or negative? I know what I think.
  18. 2012 SkS Bi-Weekly News Roundup #11
    Is there any actual solid progress being made though? While the climate science FUDers are doing their thing & large parts of the public continue to buy into that line of BS, for whatever reason - political ideology seems to be a favourite amongst those I've spoken to, I just don't see us going much of anywhere. Particularly this past year my level of pessimism has only been going up... I've reached the point where I despair for our future to be perfectly honest.
  19. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    As a working biologist/ecologist, I found the article interesting, but scant on information. It did prompt me to do a little research on the vegetation and food chain bullets. My initial reaction was that those statements did not appear to be a negative consequence of climate change and instead appeared to be generally positive. A Christmas Eve morning spent reviewing published data supported my intuition. From Environmental News Network, "Rising temperatures in the Arctic circle has caused changes in vegetation in the last few decades. Plants are growing taller, there is less bare ground devoid of vegetation, and even some shrubs are growing. It is far from being an agricultural breadbasket, but is well on its way to becoming a more lively ecosystem." The arctic fox population fluctuates based on prey availability - notably lemmings. It is a well studied and classic example of predator/prey relationships as pertaining to population sizes. Also, competition with the larger red fox has caused population decline in areas where the red fox has increased it's range. The northern limit of the red fox's geographic range is determined directly by resource availability, whereas the southern limit of the arctic fox's range is determined, through interspecific competition, by the distribution and abundance of the red fox. There are definitely climate change fingerprints on resource availability. However, it is not the only reason red fox numbers have increased. It has to be considered that the decline in gray wolf numbers has led to an increase in the number of red foxes due to decreases inter-specific competition and predation. Less gray wolves also results in fewer carcasses for arctic foxes to scavenge from. Also, a recent paper shows that climate change will favor non-specialist animals in the sub-arctic. From the paper: "The reason they expect global warming to benefit Arctic mammals rather than hinder them, they say, is that most high-latitude species are generalists: they’re used to having to cope with a wide range of climatic conditions and aren’t too dependent on any one feature of the ecosystem." Some species will decline, but many others will benefit. And, with phytoplankton being the base of the trophic level pyramid more energy will be available to move upward to larger animals. There may, or may not, be issues related to the timing of the phytoplankton bloom, but regardless aquatic and terrestrial ecosystems will be benefit. A recent paper by Arrigo, et al (2012) supports this.
  20. Solar Cycle Model fails to predict the recent warming
    @ JRT256 #18 The answer to the question, “What's the link between cosmic rays and climate change?”, is the SkS rebuttal article to the denier myth, “It’s Cosmic Rays”. To access the Intermediate version of the rebuttal article, click here To access the Advanced version of the article, click here If you have any follow-up questions about the contents of either of these two articles, please post them on the common comment thread to the articles.
  21. Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    curiousd, What is it exactly that you are asking about the hole (the inverted spike)? Yes, that is the region of CO2 absorption, but what don't you understand? Without knowing that answer, just taking a shot and hoping this answers your question: Within that range of wavelengths (or wave numbers or frequencies, depending on whichever measure is being used), CO2 strongly absorbs radiation. In the dense troposphere, such absorbed energy is usually quickly transmitted, through a collision, to another molecule, most likely O2 or N2 (those being by far the most common). This leaves the CO2 molecule capable of absorbing (and transmitting) IR once again, and also heats the atmosphere (given that the temperature of a gas is primarily a measure of the translational kinetic energy of its component molecules). At higher altitudes, where the altitude is less dense (and cooler), the CO2 molecule has more of a chance of re-emitting the absorbed radiation before passing that energy on to another molecule by collision. Even so, while it is more likely to have absorbed the energy from the warmer parts of the atmosphere below than the cooler parts above, it may radiate it away in any direction, with equal chance, so that some of the radiation arriving from from the planet below, through the atmosphere, may be radiated back down where it is more likely to be absorbed by the atmosphere and transmitted to another molecule. Eventually, of course, some of this radiation escapes into space -- but much less of it within this band than in other bands, due to all of the interference along the way. So there are two ways that you can explain this. One is to visualize the various photon-and-molecule interactions along the way, which prevent energy in that band from proceeding through unscathed (as it does in most, but not all, other bands). Another, broader way to look at it is that the energy in the IR band is dimmed, much as lighted is partially blocked, scattered and dimmed when passing through a fog. But in the case of the radiation in this band, in the atmosphere, there is eventually a point in the atmosphere where that band of radiation is being emitted and the atmosphere is rarefied enough to allow it to escape, unhindered, into space. Since this altitude is higher, that area of the atmosphere is also cooler, therefore it emits at a lower temperature and therefore it emits less total radiation (in that band). In a nutshell, then, this means that for other bands, the degree of emission (the strength in that band) conforms to the temperature at the surface of the earth (since the radiation makes it through, unhindered, from surface to space). [Study the Stefan-Boltzmann law.] The band in the absorbed-by-CO2 range, however, is hindered, and so is emitted from an area near the top of the troposphere. That area is, of course, much cooler, and so the radiation of emission represents that of a body of a much lower temperature, i.e. radiation in that band is weaker. Taking this one step further and increasing the CO2 concentration can, among other things, show that eventual transmission into space, while unaffected and so unchanged in other bands, will occur from a higher altitude in the CO2-absorption bands. This means that total energy emitted from the surface, which has warmed due to the effect, will be higher, but emission into space within the CO2 band will from an even higher, cooler altitude, and so will be reduced. [There are other details here, such as pressure and doppler broadening, which marginally widen the bands being discussed, but these details aren't strictly necessary to understanding the "hole" or "window" under discussion.]
  22. Solar Cycle Model fails to predict the recent warming
    Interesting, but aren't you beating the wrong dead horse? The question currently being asked is whether Sunspot cycles and variations in cosmic rays that accompany them are influencing the Earth's temperature and climate.
  23. Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    In the above nice graph by Conrath, et al, there is that cental up going spike that appears at the maximum absorption wavelength for the CO2 bending mode. The same thing shows up using Modtran and the spike varies in an interesting way with the simulated altitude of the satellite. If I show this to an audience someone will ask about that spike. I could guess but don't want to. Can someone explain?
  24. Dikran Marsupial at 21:43 PM on 24 December 2012
    Foster and Rahmstorf Measure the Global Warming Signal
    @curiousd Firstly it is rather overstating things to suggest that the "Foster - Rahmsdorff multiple regression analysis is one of the important parts of any AGW presentation"; it isn't, it is a useful analysis that shows that the recent "hiatus" in global temperatures can be adequately explained by the observed forcings and ENSO. If it wasn't for the "skeptics" bloviating on about the hiatus and promulgating multiple misunderstandings of statistical significance, Foster and Ragmsdorff would get far less attention that it does. The really important parts of an AGW presentation are about physics, not statistics. What Foster & Rahmsdorff are not doing is claiming that their regression analysis is a solid attribution study (as far as I can see), so it isn't that surprising that there may be other elements relevant to a proper attribution (e.g. cloud cover, aerosols etc.) that do not appear in the analysis. Regression analysis has a problem called "missing variable bias", which basically means that if one of your explanatory variables is correllated with some relevant variable that is not included in the analysis, it will act as a proxy (to some extent) for the missing variable. This means that a regression analysis can be used to show that something can be explained by X, Y and Z, but not that it is explained by X, Y and Z. This is what Foster and Rahmsdorff are aiming to do, i.e. demonstrate that observed temperatures can be explained by a linear trend, solar forcing, volcanic forcing and ENSO, and therefore there is no real reason to be greatly surprised by the apparent hiatus that is the focus of so much interest. The analysis is primarily useful in combatting misinformation.
  25. The Ridley Riddle Part One: The Red Queen
    Philippe: Ideologues pushing this nonsense in the opulent comfort of Western countries that have well established, stable, democratic goverments would be well served to go experience what life is like in countries that have no effective goverment. Basically, it's hell... Good government is like an efficiently functioning electric utility, remarkable mostly because so much of it has become invisible to us, taken for granted. We may complain about the rates we pay for electricity but what's far worse is flipping a switch and having no lights come on. Good government is like no government in the mutual feature of invisibility.
  26. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    Hmmm... I make it 2017... but we'd need to define "Ice Free" to make it more real. I am pretty sure this was done over at Tamino's site too :-) I am however, further predicting that it won't make a lick of difference to CEI, Heartland, Watts, Limbaugh, Inhofe or Monckton.
  27. Philippe Chantreau at 12:20 PM on 24 December 2012
    The Ridley Riddle Part One: The Red Queen
    I'll add that talking about entrenched individuals when discussing a US goverment agency is also moot. The leadership of these agencies is subject to the vagaries of elections and changes in fact more often than desirable for consistency and follow-up of long term actions. The 2 consecutive Bush administrations appointed leaders for the EPA under whom the enforcement process slowed to a crawl, effectively rendering the agency toothless. I note that Markx also establishes his strawman of choice by suggesting that proponents of goverment involvement have the illusion that government will always act in the interest of most people. Ridley shares in that fallacy, as far as I can tell (I don't really have the time to dwell in his ramblings). Of course, since nobdy and no group of people is perfect, this is not the case, the strawman is an especially easy one to set on fire. But that's a very different contention that saying that the overall sum of government actions will result in mostly adverse consequences, a step that Markx and Ridley seem eager to take as if it logically followed. Ideologues pushing this nonsense in the opulent comfort of Western countries that have well established, stable, democratic goverments would be well served to go experience what life is like in countries that have no effective goverment. Basically, it's hell: Life run by whatever local maffia manages to scare other groups by violence; corruption as a way of life; merit and competence relegated as useless ornaments of one's persona, because connections are the only thing that matter. I've lived on 3 continents and a large island, and visited other places too. It takes more than ideologically driven rethoric to convince me. Ideology almost never passes the test against reality. The other strawman is that any kind of new government action is a step toward non-democratic government. This argument has been around for so long that you'd swear by now we should be in a full blown dictature.
  28. Philippe Chantreau at 11:48 AM on 24 December 2012
    The Ridley Riddle Part One: The Red Queen
    Markx if you agree with all the points I made that you have listed, then you agree that your original argument, to which these points constituted a response, was bunk. Strong environmental regulations are the hallmark of free countries where citizens care about their quality of life. As for the EPA/market comparison, you are the one who brought up "entrenched individuals" bent on "enriching themselves" implying that this is what the EPA is about. I said that it was grotesque. I maintain that view and note that you have failed to provide examples of real individuals who would have verifiably conducted such evil deeds. My example, however, adapted from your piece of rethoric with a few changed nouns can be supported by actual events and actual people who have actually screwed the entire world to the point of driving some countries' economies near total collapse. That is where the comparison resides: Same language, different actors, one is real and heavily documented, the other is fed to you by ideologues and fictitious. Now, I'm sure that some instances of corruption and systemic failure can be found in the EPA process, as no human endeavor will ever be flawless. However, the consequences will be orders of magnitude smaller than the mess thrown upon us by the finance barons. And no, I am not going to list names, it can be found all over Google, books have already been written about it, etc.
  29. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Great, Dana, I'll be looking forward to it. Thanks to you and others here for the great work that you all do. I've learned a lot, although I have a lot more to go. If I can put in a request -- I'm very interested in understanding more about the physics of drought. More than just "the wet gets wetter and the dry dryer." I think this is a crucial issue that the world is going to have to face right now -- not some decades in the future. I've been reading the interesting papers of Isaac Held of the GFLD, but I'd like to know more about the assumptions that go into the various models, as well as the contradictions between models and the ramifications.
  30. 2012 SkS Bi-Weekly News Roundup #11
    Wouldn't it be nice to be able to link to an equal number of articles reporting actual, solid progress in the war on AGW? It seems all we are hearing are apologies and excuses, but no tangible deliveries. At least we in Australia can look at our brand-new carbon pricing scheme with some satisfaction. Even though it is still too little to be of significance, it does lay a foundation for future meaningful actions. With a change of government expected in 2013, can we realistically hope that the conservative side of politics will keep up the good work started by the progressives? I have a bad feeling the answer is "no".
  31. CO2 effect is saturated
    curiousd, Tom: q is almost certainly specific humidity (mass of water vapour per unit mass of moist air). Humidity units can be quite confusing - the only one that makes sense to everyone is relative humidity, and it's the one that is most useless for serious work. Other common ones: e - vapour pressure (partial pressure of water vapour) r - mixing ratio (mass of water vapour per unit mass of dry air) Td - dew point temperature (temperature at which air would reach saturation if cooled) Conversion between various forms is a common torture test subject in undergraduate meteorology courses.
  32. CO2 effect is saturated
    curiousd @193, I am not familiar with that model, so I can't be much help. However: lev = Level, numbered from the top of the atmosphere (32 km) p = atmospheric pressure at that level z = altitude in kilometers T = temperature Unfortunately I cannot help you with q.
  33. Foster and Rahmstorf Measure the Global Warming Signal
    curiousd @94, I am not up on the maths used by Foster and Rahmstorf, but my understanding is that they took four indices, one each for solar, ENSO, and volcanic activity, and a linear trend; and regressed them against the temperature record. The only check that these are all the factors involved is that the residuals have a normal distribution. Using this method, if there were a fifth factor whose activity was highly correlated with one of the four factors used by Foster and Rahmstorf, its effects would have been included with the regression of that factor. Thus, if stratospheric H2O was causing a near linear cooling trend in surface temperatures, it would have been included in the analysis simply as a reduced global warming signal (the linear trend) and the linear trend should be interpreted as the consequence of two factors (increased GHG forcing plus decreasing stratospheric H2O) rather than the consequence of one. Alternatively, as stratospheric temperatures are significantly effected by solar activity, the effect of reduced stratospheric H2O may by highly correlated with the solar signal. As Sphaerica points out, the test of this supposition would be to find an index of stratospheric H2O, and to repeat Foster and Rahmstorf's analysis with five indices rather than four.
  34. Models are unreliable
    No, Jack, you don't get a pass just because your "time is limited". You have plenty of time to type pompous assertions, so certainly you have time to at least click the links we provide you before you type more. There is no "if" about it--source code and documentation of GCMs easily are available, if you just click. We have given you links to only a subset of them. Another one is the Monash Simple Climate Model (based on GREB)--so simple that you should easily be able to confirm the quality of its code, the sensibility of the factors it includes, and the deviation from horizontal of its projections. (Hat tip to the Rabbett.) You responded "The range of uncertainty for those models is so large it doesn't really tell us anything. A result so broad that it would be difficult for it to ever be wrong is also not very right." Your statement is obviously wrong, unless you can't draw a horizontal band with your imagination, in the graphs we provided you. Well, maybe you can't, so this first figure's authors have done it for you. It would be really easy for the models to be wrong, but they aren't. Being wrong means the globe will not warm, so there's no need to do anything. In contrast, being right even at the low edge of the predictive envelope most definitely means needing to act substantively right now. When you do bother to click the links we provide, you need to then read carefully. Your interpretation of RealClimate's FAQs on GCMs as "primarily tuned by trial&error, not scientific principles [please note the word 'tuned']" is a result of your skimming when you lack the most basic prior knowledge. If you had bothered to watch the short Climate Modeling 101 videos I pointed you to, you might have had the knowledge to understand that those tunings (of which there are relatively few) are done not to make global temperature evolution match the observed evolution, but instead to make a few very narrow, specific, component, physical processes in the model match the observations about those very narrow, specific, component, physical processes. As KR responded to you, these are physical models, not statistical ones.
  35. Arctic continues to break records in 2012: Becoming warmer, greener region with record losses of summer sea ice and late spring snow
    Any predictions as to when the Arctic will be ice free in the summer? I predict 2020 for first ice free season.
  36. Foster and Rahmstorf Measure the Global Warming Signal
    Honestly if you're going to argue that changes in solar activity from over 60 years ago could be causing global warming today, you might as well argue that subterranean unicorn farts are causing global warming too. Just because we can't conclusively disprove something doesn't mean that it's remotely physically plausible.
  37. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Note that I've got a comprehensive blog post and rebuttal to the myth that the IPCC overestimated global warming (the argument based on Figure 1.4) in the works. It should be published next week. And it's pretty darn good, if I do say so myself.
  38. Models are unreliable
    JackO'Fall - "...re-running a 2004 scenario (for example), yet adding in 'known future' levels of things like CO2 and volcano emissions. If that exists, please let me know." See Comparing climate projections to observations up to 2011, Rahmstorf et al 2011, which does exactly that. "...they (models) are primarily tuned by trial&error, not scientific principles [please note the word 'tuned']" I would have to call this an incorrect assertion based upon not knowing how these models are developed - ie, from the physics. "What I was referring to is a lack of source-code with documentation for the GCMs. If it exists, I am clearly wrong and fully retract that statement." See the RealClimate links for GCM model codes, also radiative transfer models and others. Again, these are widely available, and have always been. "The range of uncertainty for those models is so large it doesn't really tell us anything. A result so broad that it would be difficult for it to ever be wrong is also not very right." On the contrary - predictions of climate change due to anthropogenic influence data back 120 years, and have been demonstrated to be correct over and over again. --- To be blunt, Jack, you have made a long list of assertions that are (a) wholly incorrect, and (b) you would have found to be so with only a little effort in looking things up. I strongly suggest you do a bit more reading.
  39. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Mighty Drunken @22 & @24 You raised the same point that I did, which is that it is difficult to claim that Figure 1.4 of the draft shws the data right in the middle of the scenarios. If you're still following this thread Tamino has an excellent discussion of this exact point and shows that the problem is that the draft aligns all the projections at 1990, a warm year, rather than to a trend line to the data. In brief, this resolves the discrepancy between the draft report and what Dana is showing above.
  40. Foster and Rahmstorf Measure the Global Warming Signal
    Sphaerica, the link below seems to work for me: http://www.heatisonline.org/contentserver/objecthandlers/index.cfm?ID=7634&Method=Full That being said, when someone uses the phrase
    "...my imaginary denialist is now asking me..."
    it raises the hackles on the back of my neck.
  41. Foster and Rahmstorf Measure the Global Warming Signal
    curiousd, Please provide a working link. I'm also confused by the wording of your "argument." "Has allowed?" It passed peer review, that's all. That doesn't make it true, that just makes it good enough for everyone to decide if it's true. What are the published comments on the paper? Have subsequent papers been published that rebut it? Is it being properly interpreted in this context? I personally have never seen such an argument, and even if it is, I don't necessarily see it as incompatible with F&R 2012. My next step would be to see if, when adding stratospheric water vapor to the F&R methodology, how much and in what direction it contributes.
  42. Foster and Rahmstorf Measure the Global Warming Signal
    I find myself these days asking the question...."What would be hard questions to handle if a denialist queries part of my presentation on AGW?" Since the Foster - Rahmsdorff multiple regression analysis is one of the important parts of any AGW presentation,IMO, my imaginary denialist is now asking me: "The establishment, peer reviewed literature has allowed publication of an article to the effect that lessening of stratospheric water vapor has temporarily slowed global warming ...see http://www.heatisonline.org/contentserver/objecthandlers/index.cfm?ID=7634&Method=Full.... SKS had no particular quarrel with this article, I recall; only in its over interpretation by others. Then why is this effect of lessening stratospheric water vapor (apparently) completely removed by the method of Foster and Rahmsdorff?
  43. Models are unreliable
    Jack, Anyone who has looked at this issue at all should know that GISTEMP has two web links. One gives their code and documentation for determining the anomaly of surface temperatures and the other gives code and documentation for their climate model. That includes all the source code and documentation that you can desire,including old models. You need to do your homework before you criticize hard-working scientists efforts. Look at GISS again and find the climate model link.
    Moderator Response: [TD] Typo: "GISTEMP has two web links" should be plain "GISS."
  44. Models are unreliable
    @ Tom Dayton: I never said a modeler doesn't want to improve their model, just that I would like them to continuously improve and that the need to include new feedbacks is not bad. I threw that in there in hopes of showing that I'm not rooting against the models. Apparently I missed getting that across. My apologies. My time is limited, so I know I miss a lot of data out there (and don't have a chance to reply to a lot of what gets written back at me). However, I looked at the GISTEMP link, it doesn't look like a climate model, but an attempt to recreate the corrective actions that go into adjusting the raw data from the temperature stations and producing the GISS results. Still, cool that they are doing it. What I was referring to is a lack of source-code with documentation for the GCMs. If it exists, I am clearly wrong and fully retract that statement. I also read the RealClimate FAQs on GCMs, as suggested. It seemed to agree with many of my basic contentions. (they have estimations that they know are off, they don't include everything we know, they are prone to drifting-though less than in the past, they are primarily tuned by trial&error, not scientific principles [please note the word 'tuned']) @KR: While both of Hansen's graphs seem to do a good job estimating future temperatures, that's not what I was referring to. I believed Tom Curtis was proposing re-running a 2004 scenario (for example), yet adding in known 'future' levels of things like CO2 and volcano emissions. If that exists, please let me know. Of course, the other link was inconclusive, so be polite. The range of uncertainty for those models is so large it doesn't really tell us anything. A result so broad that it would be difficult for it to ever be wrong is also not very right. @scaddenp: At the very least, if the ENSO correction is more natural variability than previously understood, that is very helpful. In terms of modeling that, it will probably increase the uncertainty range, but would allow for a better run at what I believe Tom Curtis proposed. That may be more helpful in time scales of less than 30 years (I'm not sure anyone will wait 30 years to see if the current models accurately predicted the future). My apologies for off-topic discussion. I should not have made my initial off-the-cuff economic response, and certainly should not have replied more extensively.
  45. Matt Ridley Risk Management Failure Deja Vu
    KR @ a2, thank you for posting the graph. The caption makes sense now.
  46. 2012 SkS Weekly Digest #50
    Bernard J. @ 13, why didn't I think of that? Doh! Thank you. vrooomie @ 14, on my tight budget, that is a luxury I will have to forego. With any luck, the State Library service will be able to track down a copy for me.
  47. Matt Ridley Risk Management Failure Deja Vu
    John Russell astutely commented:
    "...optimists... [are] ...generally healthier and happier than pessimists..." They are until overtaken by events they didn't foresee due to their irrational optimism. It's interesting that there are so many optimists around -- I'd have thought that, thanks to evolution, we'd have lost them all to lions hiding behind rocks.
    This reminds me of Douglas Adams' observation on the phenomenon, which most people blithely assume is simply a comic instrument:
    The Book: It is important to note that suddenly, and against all probability, a sperm whale had been called into existence, several miles above the surface of an alien planet. And since this is not a naturally tenable position for a whale, this innocent creature had very little time to come to terms with its identity. This is what it thought, as it fell: The Whale: Ahhh! Woooh! What's happening? Who am I? Why am I here? What's my purpose in life? What do I mean by who am I? Okay okay, calm down calm down get a grip now. Ooh, this is an interesting sensation. What is it? Its a sort of tingling in my... well I suppose I better start finding names for things. Lets call it a... tail! Yeah! Tail! And hey, what's this roaring sound, whooshing past what I'm suddenly gonna call my head? Wind! Is that a good name? It'll do. Yeah, this is really exciting. I'm dizzy with anticipation! Or is it the wind? There's an awful lot of that now isn't it? And what's this thing coming toward me very fast? So big and flat and round, it needs a big wide sounding name like 'Ow', 'Ownge', 'Round', 'Ground'! That's it! Ground! Ha! I wonder if it'll be friends with me? Hello, Ground! [Cuts to a distant view as the whale hits the ground and spews up a large mushroom cloud of snow] The Book: Curiously, the only thing that went through the mind of the bowl of petunias, as it fell, was, "Oh no, not again!" Many people have speculated that if we knew exactly *why* the bowl of petunias had thought that we would know a lot more about the nature of the universe than we do now.
  48. Solar Cycle Model fails to predict the recent warming
    Philip: comments in journals are actually a fairly rare thing, and a lot of journals don't really like them much. Some may not allow them at all. It can also be a lot of work to prepare one, and you don't get much credit as an academic for them. To advance a career, time is better spent on full articles - but for that to be a "response" to a bad paper, it has to have enough new stuff in it to merit publication on its own (but then can also be submitted to any journal you want, not just the one with the bad paper). For a bad paper in an odd journal, the editors may not want to publicly acknowledge that they let utter crap through their peer review process - which may mean that the subject was one they didn't really know much about to begin with (and therefore can't judge the merits of the comment, either). You'll see frequent mention here at SkS by dana1981 to the paper discussed in the post Nuccitelli et al. (2012) Show that Global Warming Continues. That was published as a comment, but the original idea was (I think) to submit it as a stand-alone paper, and the journal/editor decided it was more suited as a comment. Dana may wish to weigh in on the difficulties of the process.
  49. Matt Ridley Risk Management Failure Deja Vu
    I really don't understand the likes of Ridley. This year in the UK we started with drought, now we have to much water everywhere and we are no where near seeing the worst of climate change! There are businesses really suffering as well as home owners. The risk is clear in the UK, do nothing and the costs are going to be astonishing.
  50. Solar Cycle Model fails to predict the recent warming
    HPJ@12, I hope it's not amiss to ask a question about scientific publication protocol rather than climate: Why not send a comment to the journal? Granted, the information is now out in the world, but it's not right in front of the people who saw the original article. And it doesn't seem to me that it would need to be anything elaborate, just 'Adding solar cycle numbers to the dots in their figure X (see figure Y) shows that their model fails increasingly badly after solar cycle 20.' And a reference to this posting. At worst you waste a couple of hours. At best you can point out to deniers and journalists that SSH have been shot down where they were originally published. Granted, I may completely underestimate the difficulties, but that's why I'm asking.

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